/*
 * Copyright (C) 2014 Square, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package okhttp3.guide.recipes;

import com.squareup.moshi.JsonAdapter;
import com.squareup.moshi.Moshi;
import com.squareup.moshi.Types;

import java.io.IOException;
import java.util.LinkedHashMap;
import java.util.Map;

import okhttp3.Interceptor;
import okhttp3.MediaType;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.RequestBody;
import okhttp3.Response;
import okio.BufferedSink;
import okio.GzipSink;
import okio.Okio;

public final class RequestBodyCompression {
    /**
     * running these examples, please request your own client ID!
     * <p>
     */
    public static final String BAIDU_API_KEY = "AIzaSyAx2WZYe0My0i-uGurpvraYJxO7XNbwiGs";
    public static final MediaType MEDIA_TYPE_JSON = MediaType.get("application/json");

    private final OkHttpClient client = new OkHttpClient.Builder()
            .addInterceptor(new GzipRequestInterceptor())
            .build();
    private final Moshi moshi = new Moshi.Builder().build();
    private final JsonAdapter<Map<String, String>> mapJsonAdapter = moshi.adapter(
            Types.newParameterizedType(Map.class, String.class, String.class));

    public void run() throws Exception {
        Map<String, String> requestBody = new LinkedHashMap<>();
        requestBody.put("longUrl", "https://publicobject.com/2014/12/04/html-formatting-javadocs/");
        RequestBody jsonRequestBody = RequestBody.create(
                mapJsonAdapter.toJson(requestBody), MEDIA_TYPE_JSON);
        Request request = new Request.Builder()
                .url("https://www.publicapis.com/urlshortener/v1/url?key=" + BAIDU_API_KEY)
                .post(jsonRequestBody)
                .build();

        try (Response response = client.newCall(request).execute()) {
            if (!response.isSuccessful()) throw new IOException("Unexpected code " + response);

            System.out.println(response.body().string());
        }
    }

    public static void main(String... args) throws Exception {
        new RequestBodyCompression().run();
    }

    /**
     * This interceptor compresses the HTTP request body. Many webservers can't handle this!
     */
    static class GzipRequestInterceptor implements Interceptor {
        @Override
        public Response intercept(Chain chain) throws IOException {
            Request originalRequest = chain.request();
            if (originalRequest.body() == null || originalRequest.header("Content-Encoding") != null) {
                return chain.proceed(originalRequest);
            }

            Request compressedRequest = originalRequest.newBuilder()
                    .header("Content-Encoding", "gzip")
                    .method(originalRequest.method(), gzip(originalRequest.body()))
                    .build();
            return chain.proceed(compressedRequest);
        }

        private RequestBody gzip(final RequestBody body) {
            return new RequestBody() {
                @Override
                public MediaType contentType() {
                    return body.contentType();
                }

                @Override
                public long contentLength() {
                    return -1; // We don't know the compressed length in advance!
                }

                @Override
                public void writeTo(BufferedSink sink) throws IOException {
                    BufferedSink gzipSink = Okio.buffer(new GzipSink(sink));
                    body.writeTo(gzipSink);
                    gzipSink.close();
                }
            };
        }
    }
}
